1. Field of the Invention
The present invention relates to a vehicle charging system.
This application claims priority from Japanese Patent Application No. 2011-008697 filed on Jan. 19, 2011, the contents of which are incorporated herein by reference in their entirety.
2. Background Art
Conventionally, as charging cables used for charging a battery of an electric vehicle from a power source (external power source) provided outside a vehicle such as an alternating-current source used for household or the like, charging cables are well-known in which a period of charging time or charging start time can be determined or charging mode can be switched (for example, refer to Japanese Unexamined Patent Application, First Publication No. 2009-100569).
Additionally, a charging control apparatus is conventionally known in which pilot signals output from an oscillator provided inside an electric power cable are used for, for example, a signal indicating activation of a vehicle charging system (for example, refer to Japanese Unexamined Patent Application, First Publication No. 2009-171733).
However, the above-described conventional charging cable or electric power cable is provided with a charging circuit interrupt device (CCID) that detects a connection state between a charging cable and a vehicle charging system, that interrupts the connection between an external power source and a vehicle charging system when overcurrent or leaking of electrical current is generated, or the like.
Consequently, activation of the vehicle charging system is controlled by control pilot signals (CPL signal: Control Pilot Line signal) output from the charging circuit interrupt device.
However, according to the aforementioned conventional charging cable or the electric power cable, the interrupting current value of the charging circuit interrupt device is only determined in accordance with the interrupting current value of a relay or the like provided at the charging circuit interrupt device, and the interrupting current value is not reflected to the allowable electric power that the external power source can supply.
Because of this, in the external power source such as an alternating-current source used for household or the like, in which, for example, the allowable electric power which can be supplied by the external power source varies depending on consumed power in a house, there is a concern that an amount of the electric power exceeding the amount of the allowable electric power which can be supplied is extracted as charging power from the external power source.
In this case, there is a concern that the electric power supplied from the external power source inclusively power feeding in home is broken by a current limiter (or breaker) provided at the external power source.
As a countermeasure against the foregoing problems, for example, when the breaking current value of the external power source is made sufficiently-high, there is a problem in that required cost of device constitution or required cost of consumption of electric power increases.